我如何允许存储我的列表视图，以便我可以从另一个类或表单中显示

Question

{
public partial class BookNow : Form
{
    private const int CP_NOCLOSE_BUTTON = 0x200;
    private string title;
    private string ad;  //Adult
    private string ch;  //Child
    private string sd;  //StartDate
    private string rd;  //ReturnDate
    private string ins; //Insurance
    private string extb; //Extra Baggage
    private int people;
    private double total = 0;
    Cart c = new Cart();
    ArrayList arr = new ArrayList(30);


    public BookNow()
    {
        InitializeComponent();
        adult.SelectedIndex = 1;
        child.SelectedIndex = 0;
        insuranceNo.Checked = true;
        tenKG.Checked = true;
    }

    private void Next_Click(object sender, EventArgs e)
    {
        if (tour.Text == "Choose A Tour")
        {
            MessageBox.Show("Please select a tour of your choice", "Choice of Tour Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            tour.Focus();
        }
        else if (adult.Text == "0" && child.Text == "0")
        {
            MessageBox.Show("Please select number of Travellers", "Number of Travellers Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            adult.Focus();
        }
        else if (startDate.Text == returnDate.Text)
        {
            MessageBox.Show("Start Date and Return Date Cannot be the Same. Please Edit Dates to Continue", "Dates Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            returnDate.Focus();
        }
        else
        {
            if (tour.Text == "TSIN - Singapore's Discovery")
                total += 1299.00;
            else if (tour.Text == "TSEO - Seoul's Highlights")
                total += 1899.00;
            else if(tour.Text == "TTAI - Taiwan Spotlight")
                total += 1000.00;

                title = tour.Text;
                ad = adult.Text;
                ch = child.Text ;
                sd = startDate.Text;
                rd = returnDate.Text;
            if (insuranceYes.Checked)
            {
                ins += insuranceYes.Text;
                total += 29.99;
            }
            else
            {
                ins = insuranceNo.Text;
            }

            if (tenKG.Checked)
                extb = tenKG.Text;
            else if (twentyKG.Checked)
            {
                extb = twentyKG.Text;
                total += 50.00;
            }
            else
            {
                extb = thirtyKG.Text;
                total += 80.00;
            }
            people = int.Parse(ad) + int.Parse(ch);
            total = total * people;
            cartNow(c);
            total = 0;
            var result = MessageBox.Show("Added To Cart, Continue To Your Cart?","Cart Updated",  MessageBoxButtons.YesNo, MessageBoxIcon.Information);
            if (result == DialogResult.Yes)
            {
                c.add(c);
                Hotel h = new Hotel();
                h.Show();
            }
        }
    }

    private void Reset_Click(object sender, EventArgs e)
    {

    }

    private void Cart_Click(object sender, EventArgs e)
    {
        c.Show();
    }

  

此方法是添加到我的列表视图中，以便我可以显示并尝试使用数组但仍无法执行此操作

    public void cartNow (Cart instance)
    {
        ListViewItem lvl = new ListViewItem(arr[0].ToString());
        lvl.SubItems.Add(arr[1].ToString());
        lvl.SubItems.Add(ch);
        lvl.SubItems.Add(sd);
        lvl.SubItems.Add(rd);
        lvl.SubItems.Add(ins);
        lvl.SubItems.Add(extb);
        lvl.SubItems.Add(total.ToString("c2"));
        instance.listView1.Items.Add(lvl);

    }

    private void Close_Click(object sender, EventArgs e)
    {
        var confirmResult = MessageBox.Show("Closing the booking System will result in clearing the Cart.","Are You sure you want to continue?",
                                 MessageBoxButtons.YesNo);
        if (confirmResult == DialogResult.Yes)
        {
            this.WindowState = FormWindowState.Minimized;
            this.ShowInTaskbar = false;
        }
    }

    public void showCart()
    {
        c.Show();
    }

    protected override CreateParams CreateParams
    {
        get
        {
            CreateParams myCp = base.CreateParams;
            myCp.ClassStyle = myCp.ClassStyle | CP_NOCLOSE_BUTTON;
            return myCp;
        }
    }
}
}

  

我可以打开我的购物车并显示我的列表视图中的项目，但是当我关闭购物车并想要从另一个表单运行时，它不起作用，因为信息变空，例如（具有成人数量的可变广告）变为null，如果我尝试从另一个类

运行cartNow（）方法，将显示第n个